Question 900
At Pinecrest logistics, in a sandbox Kubernetes cluster during a recovery tabletop exercise: Pod dispatch-api in fulfillment is Pending because it requires workload=restricted and no eligible Ready nodes carry that label. Work only within the stated target and verify before declaring success. Which operational control most directly prevents this failure or configuration drift?
Explanation
Correct Answer
Govern scheduler labels and include eligible-node checks before promoting hard node selectors. This reduces recurrence of the specific operational failure. It reinforces the action: Run kubectl get nodes -l workload=restricted and compare with kubectl -n fulfillment describe pod dispatch-api before changing node labels. The relevant mechanism is: A hard nodeSelector must match a Node's actual labels; tolerations or Service routing cannot bypass the unmatched selector.
Incorrect Answers
The suggested review tracks a different technical risk: A PVC binds only to compatible available storage or successful dynamic provisioning; absent provisioners, quotas or delayed binding can leave it Pending. Here the sustained control must address: A hard nodeSelector must match a Node's actual labels; tolerations or Service routing cannot bypass the unmatched selector. Choose “Govern scheduler labels and include eligible-node checks before promoting hard node selectors”.
That safeguard is relevant to: A Deployment selector identifies Pods it owns and is generally immutable after creation; patching Service selectors alone does not repair ownership. The current failure instead follows from: A hard nodeSelector must match a Node's actual labels; tolerations or Service routing cannot bypass the unmatched selector. Its prevention measure is “Govern scheduler labels and include eligible-node checks before promoting hard node selectors”.
This routine guards against another mechanism: Kubernetes network connectivity requires a functioning CNI implementation on nodes; core API objects alone do not create functional Pod networking. The recurring exposure in the current case is: A hard nodeSelector must match a Node's actual labels; tolerations or Service routing cannot bypass the unmatched selector. The matching preventive check is “Govern scheduler labels and include eligible-node checks before promoting hard node selectors”.